Effect of a 6-Week Quadriceps and Hip-Abductor Strengthening Programme on Pain, ROM and Function in Knee Osteoarthritis

Knee osteoarthritis (OA) is one of the most common reasons adults over 45 attend a physiotherapy outpatient department in India. Squatting, floor sitting, cross-legged sitting and climbing stairs in multi-storey homes all load the medial tibiofemoral compartment, and many patients arrive with months of pain, stiffness and difficulty rising from the floor. Clinical guidelines rank exercise therapy as first-line management, but most OPD programmes focus only on the quadriceps and ignore the hip abductors, which control pelvic drop and knee adduction moment during walking.

This project is a single-group pre–post interventional study in which 30 patients with radiologically confirmed knee OA (Kellgren–Lawrence grade II–III) follow a supervised 6-week programme combining quadriceps and hip-abductor strengthening, three sessions a week. Pain is measured on the Numeric Pain Rating Scale (NPRS), knee flexion range of motion with a universal goniometer, function with the WOMAC index, and mobility with the Timed Up and Go (TUG) test — at baseline and after six weeks.

The study is designed for the BPT final-year research project under RGUHS / KUHS / MUHS-type health-science university schemes: a group of three students, a guide, Institutional Ethics Committee approval, written informed consent, a bound report and a viva. Data are analysed with the paired t-test (or Wilcoxon signed-rank test if data are not normal) in SPSS or Jamovi.

Abstract

Thirty participants aged 45–70 years with unilateral or bilateral knee OA (Kellgren–Lawrence grade II–III) were recruited from the physiotherapy OPD of a teaching hospital by consecutive sampling. After baseline assessment of NPRS, active knee flexion ROM, WOMAC total score and TUG, they completed a supervised 6-week quadriceps and hip-abductor strengthening programme (three sessions per week, 45 minutes each) with a home programme on the remaining days. Outcomes were re-assessed at the end of week 6. Pre and post values were compared with the paired t-test or Wilcoxon signed-rank test at p < 0.05.

Introduction

OA is a degenerative joint disease characterised by cartilage loss, subchondral bone changes and synovial inflammation. Quadriceps weakness is both a consequence and a risk factor for progression. Weak hip abductors allow the pelvis to drop on the swing side and increase the external knee adduction moment, which loads the medial compartment. Strengthening both groups is therefore biomechanically rational and cheap enough for Indian OPDs.

Review and gap

Randomised trials abroad show that hip-strengthening added to quadriceps training reduces pain in medial knee OA. Indian studies mostly test quadriceps isometrics with or without electrotherapy, and few report WOMAC together with ROM and TUG in the same cohort. A pre–post study in a local OPD population is a practical first step and generates effect-size data for a later controlled trial.

Hypotheses

• H0: there is no significant difference between pre- and post-intervention NPRS, ROM, WOMAC and TUG scores.
• H1: the programme significantly reduces pain and WOMAC scores and improves ROM and TUG.

Feasibility

• Technical: goniometer, cuff weights, resistance bands and printed scales are available in every BPT teaching OPD.
• Economic: under ₹3,000 for bands, printing and consent forms.
• Time: eight weeks of recruitment and intervention fit inside the internship-year project window, leaving four weeks for analysis and writing.
• Ethical: low-risk exercise intervention; IEC approval and written informed consent obtained before recruitment.

Patients with knee osteoarthritis form a large share of physiotherapy OPD caseload in India, and daily activities such as squatting, floor sitting and stair climbing aggravate their pain and restrict function. Routine OPD exercise protocols often prescribe only quadriceps isometrics and straight-leg raises, while the hip abductors — which influence knee loading during gait — are rarely trained. There is limited local evidence on whether a combined, supervised quadriceps and hip-abductor programme produces measurable changes in pain, knee range of motion, self-reported function and mobility within a practical six-week period.

This study therefore asks: in adults with grade II–III knee OA attending a physiotherapy OPD, does a 6-week combined quadriceps and hip-abductor strengthening programme significantly reduce pain (NPRS) and WOMAC scores and improve knee flexion ROM and TUG time?

In scope

• Adults aged 45–70 years with clinically and radiologically diagnosed knee OA (Kellgren–Lawrence II–III).
• One OPD setting, consecutive sampling, 30 participants.
• Supervised strengthening three days a week for six weeks, with a written home programme.
• Outcomes: NPRS, goniometric knee flexion, WOMAC, TUG.

Out of scope

• A control group or randomisation (listed as future scope).
• Electrotherapy, manual therapy, bracing or injections as part of the protocol.
• Long-term follow-up beyond six weeks and radiological progression.

Study design: quasi-experimental single-group pre-test/post-test design.

Setting: physiotherapy OPD of a tertiary-care teaching hospital attached to the college.

Sampling: consecutive sampling of eligible patients until the sample is complete.

Sample size: 30 participants. Using a paired design with an expected mean NPRS reduction of 1.5 points (SD of change 2.5), α = 0.05 and power 80%, the calculation gives about 24; adding 20% for drop-outs gives 30. The expected values are taken from published strengthening trials and should be replaced with your own pilot data.

Inclusion criteria: age 45–70; knee OA by ACR clinical criteria with Kellgren–Lawrence grade II–III on X-ray; knee pain NPRS ≥ 3 for at least three months; able to walk independently; willing to attend three sessions per week.

Exclusion criteria: intra-articular injection in the past three months; knee surgery or arthroplasty; inflammatory arthritis; recent lower-limb fracture; neurological deficit; uncontrolled hypertension or cardiac disease; cognitive impairment preventing consent.

Intervention (weeks 1–6): warm-up cycling 5 min; quadriceps sets, straight-leg raise, terminal knee extension with band, mini-squats to 30°, step-ups; side-lying hip abduction, clamshells, standing hip abduction with band; 3 sets × 10 repetitions progressing load by the 10-RM rule every two weeks; cool-down stretching of hamstrings and calf.

Outcome measures: NPRS (0–10), active knee flexion ROM (goniometer, supine, average of three trials), WOMAC (pain, stiffness, function), TUG (seconds, average of two trials).

Ethics: approval from the Institutional Ethics Committee before recruitment; participant information sheet and written informed consent in English and the local language, following the ICMR National Ethical Guidelines (2017); confidentiality by coded IDs.

Statistical analysis: normality by Shapiro–Wilk; paired t-test for normally distributed variables and Wilcoxon signed-rank test otherwise; effect size by Cohen's d; significance at p < 0.05, using SPSS or Jamovi.